Micro-electromechanical systems, or here more specifically micro-electromechanical switch elements, referred to hereinafter as MEMSs, are a possible replacement for conventional circuit breakers in electric power distribution systems, particularly in the low-voltage range. Since a MEMS-type single switch element has microscopic dimensions, typically in the order of several 10 μm, the electric strength is limited to a typical range of 50-100 V. In addition, the current-carrying capacity of these MEMSs restricts the field of application to typically less than 100 mA. This means that, in practice, to enable higher currents to be switched when used as circuit breakers, it is necessary for a plurality of these MEMSs to be arranged electrically in parallel in a circuit.
Since, in low-voltage switching technology, it is also necessary to handle higher voltages in the 700 V to 1000 V range, it is also necessary for a corresponding number of MEMSs to be arranged electrically in series. Manufacturing tolerances and fluctuations in the switching process, for example different contact resistances or different switching times due to contact sticking, cause a different voltage and current distribution to prevail between switches. This in turn has the result that some elements can be overloaded, which is manifested, for example, as sticking of switching contacts or fusion if arcing occurs. This would greatly reduce the expected lifetime of the MEMS or the plurality of MEMSs.